The direct drive wind turbine concept is commonly known. Several embodiments of this concept can be found in the design study NREL/SR-500-35524. All those direct drive embodiments use a generator with a stator in a stator house which is fixed to the nacelle. In this patent text the term “housing” can refer to the stator house or to the rotor house or to both. The stator comprises inter alia windings and laminations. The rotor of the generator may comprise windings or permanent magnets, both options can be combined with a lamination package. The lamination package of the rotor is fixed to a rotor house which is fixed to the rotor blades via several connection means. For several known types of generators we refer to ‘Permanent Magnet Synchronous Motor for Industrial Inverter Applications’, PhD thesis, Tanja Heikkilä, Lappeenranta Univ. of Techn.